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CVE-2021-26427

CVSS 3.1: 9.0 critical
EPSS: <1%p57
Published: Oct 13, 2021 · Oct 13, 2021
Modified: Jun 17, 2026

Analyze CVE-2021-26427 with Vani AIImpact, affected versions, exploitation status, mitigations and detection

Description · NVD

Microsoft Exchange Server Remote Code Execution Vulnerability

Vendors: microsoft

Products: exchange server

Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

NVD CVE.org GitHub PoCs EPSS (0.9%)

In the news

4 stories

Patch Tuesday, October 2021 Edition

Krebs on SecurityOct 15, 00:00 UTC · Oct 15, 2021VulnerabilityCVE-2021-30883 CVE-2021-38672 CVE-2021-40461+35 · 1 read

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Update Your Windows PCs Immediately to Patch New 0

The Hacker NewsOct 15, 00:00 UTC · Oct 15, 2021VulnerabilityExploitedCVE-2021-40449 CVE-2021-41335 CVE-2021-40469+102 · 1 read

60

Microsoft Patch Tuesday for Oct. 2021 — Snort rules and prominent vulnerabilities

Cisco TalosOct 12, 17:33 UTC · Oct 12, 2021VulnerabilityExploitedCVE-2021-40461 CVE-2021-38672 CVE-2021-40449+61

60

Microsoft patches actively exploited Windows zero-day (CVE-2021-40449)

Help Net SecurityOct 12, 00:00 UTC · Oct 12, 2021Exploit / PoCExploitedCVE-2021-40449 CVE-2021-40486 CVE-2021-26427+52 · 1 read

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